Answer:
1. Preterite
2. Imperfect
3. Imperfect
4. Imperfect
5. Preterite
6. Preterite
7. Preterite
8. Imperfect
9. Preterite
10. Imperfect
11. Preterite
12. Preterite
13. Preterite
Time cues such as length of time, or a specific year, season, month, day, or time of day indicate that we should be using the preterite.
Words such as "always," "frequently," "generally," "never," "often," "usually," "used to," and "would" clue us into the fact that we should use the imperfect.